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Area Forecast Discussion (AFD)

Issued by San Diego, CA (SGX)

                            
824 
FXUS66 KSGX 252000
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
100 PM PDT Mon Mar 25 2019

.SYNOPSIS...
The dry and mild Spring weather will persist through Tuesday, along 
with increasing high clouds as a low pressure trough moves inland to 
the north. Onshore flow will increase Wednesday, spreading cooling 
inland, along with a small chance of scattered, light showers. An 
approaching ridge will begin a warming trend on Friday, that will 
carry us through the weekend, along with plenty of sunshine each day.

&&

.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...

It was mostly clear across SoCal midday. Surface pressure gradients 
were weak and winds mostly light. Satellite imagery showed a band of 
clouds advancing slowly SE into the San Francisco Bay area, but well 
offshore farther to the south.  

A weak ridge aloft will move east tonight as low pressure off the 
PacNW coast drifts slowly east. Precipitation associated with the 
storm system will spread SE across northern and central parts of the 
State through Wednesday, possibly reaching SoCal Wed night/Thu 
morning. For now, any amounts look very light as onshore flow ramps 
up and the marine layer spreads clouds and fog back onto the coastal 
mtn slopes.

The 12Z global model runs show fair agreement now in weakening the 
low as it slides inland beneath the strong west Canadian ridge this 
coming weekend. This in tern, has increased confidence in keeping 
the weekend dry and mild with little impactful weather expected. The 
GFS keeps the weather dry early next week, but the ECMWF turns wet. 
This is beyond the current forecast period so we will have some time 
to sort it out.

Today looks to be the warmest day of the week, with only slight 
cooling on Tuesday. Wednesday and Thursday will be the coolest days, 
along with gusty winds over the mts and deserts. Daytime temps 
should be about average by Friday, then back above by a few degrees 
over the weekend. A wind advisory may be needed at some point for 
the gusty onshore winds late Wed/Thu.

&&

.AVIATION... 
251915Z...Coast/Valleys...Clear skies will prevail for the rest of 
today and tonight. Low confidence that patchy and intermittent low 
clouds could redevelop after 05Z tonight 1500 ft MSL and below at 
KSAN, KCRQ, and KSNA.  

Mountains/Deserts...Clear skies expected through tomorrow. 

&&

.MARINE...
No hazardous marine weather is expected today and Tuesday. There is 
a slight chance of isolated showers late Wednesday into Thursday, 
rain is not expected to be significant. A passing storm system will 
bring northwest winds of 12-15 kts with gusts to 20 kts Thursday 
evening. These conditions may be hazardous for small craft. 

&&

.SKYWARN... 
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.

&&

$$

PUBLIC...10
AVIATION/MARINE...CO/PG